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Full catalog/MYD05_L2
MYD05_L2·v6.1·dataset

Total water vapor in the air column (Aqua, 1-5 km)

MODIS/Aqua Total Precipitable Water Vapor 5-Min L2 Swath 1km and 5km
atmosphere NASA LAADS Level 2 active HDF-EOS
In plain English

What it measures. How much water vapor is in the entire column of air from the ground up to space, measured along the satellite's path at 1 km and 5 km detail.

How it's made. Derived from the MODIS instrument on the Aqua satellite using two methods: a daytime near-infrared approach over clear land and an infrared approach that works day and night.

How & where you'd use it. Supports weather forecasting, humidity studies, and correcting other satellite measurements that are affected by water vapor.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › HUMIDITYATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › TOTAL PRECIPITABLE WATERATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR PROFILES

Coverage & cadence

  • Time span2002-07-04 → ongoing
  • Measured byAqua (MODIS)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS
  • StatusACTIVE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

The MODIS/Aqua Total Precipitable Water Vapor 5-Min L2 Swath 1km and 5km (MYD05_L2) product consists of atmospheric column water-vapor amounts. This product is derived from data collected by the Moderate-Resolution Imaging Spectroradiometer (MODIS) on board the Aqua satellite. There are two different algorithms used to derive total precipitable water vapor in this data product: a near-infrared algorithm and an infrared algorithm. The near-infrared algorithm relies on observations of reflected solar radiation in MODIS's near-infrared channels, thus, the near-infrared retrievals are only produced during the daytime over surfaces that reflect near-infrared energy. As a result, the near-infrared algorithm is only applied over clear, cloud free land areas of the globe and above clouds over both the land and ocean. Over clear ocean areas, water-vapor estimates are provided over extended sun glint areas. Data produced by the near-infrared algorithm are generated at a 1-km spatial resolution. The other algorithm is the infrared algorithm which can be used to derive atmospheric precipitable water vapor profiles during both day and night. Data from the infrared algorithm are generated at a 5-km spatial resolution when at least nine field of views (FOVs) are cloud free. The infrared-derived precipitable water vapor is generated as a component of product MYD07, and is simply added to product MYD05 for convenience. There are two MODIS Precipitable Water Vapor products: MOD05_L2, containing data collected from the Terra platform; and MYD05_L2, containing data collected from the Aqua platform. This dataset has a short name of MYD05_L2 and provides data from the Aqua platform only. The MODIS Adaptive Processing System (MODAPS) is currently generating an improved version 6.1 (061) for all MODIS Level-1 (L1) and higher-level Level-2 (L2) & Level-3 (L3) Atmosphere Team products. The decision to create a new improved Collection 6.1 (061) was driven by the need to address a number of issues in the current Collection 6 (006) Level-1B (L1B) data, which have a negative impact in varying degrees in downstream products. It should be noted that the near-infrared algorithm refinement for this product is no longer being supported by NASA and as such there has been no update to this algorithm for Collection 6.1. For more information, visit the MODIS Atmosphere website at: https://modis-atmos.gsfc.nasa.gov/products/water-vapor

Get the data

myd05_l2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MYD05_L2",
    version="6.1",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LAADS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.